Class 12 Chemistry - Chapter General Principles and Processes of Isolation of Elements NCERT Solutions | Why is the extraction of copper from pyr
Why is the extraction of copper from pyrites more difficult than that from its oxide ore through reduction?
The Gibbs free energy of formation (ΔfG) of Cu2S is less than that of H2S and CS2. Therefore, H2 and C cannot reduce Cu2S to Cu.
On the other hand, the Gibbs free energy of formation of Cu2O is greater than that of CO. Hence, C can reduce Cu2O to Cu.
C(s) +Cu2O(s) → 2Cu(s) + CO(g)
Hence, the extraction of copper from its pyrite ore is difficult than from its oxide ore through reduction.
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5 Comment(s) on this Question
The value of âfG â for formation of Cr2O3 is -540 KJ mol-1 and that of Al2O3 -827 KJ mol-1 . Is the reduction of Cr2O3 possible with Al ?
Ok partha,you try your best
Bahot hi aacha
Nice answer
Nice answer .could hav tried litle mich better
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